/Engine/Source/Runtime/GeometryCore/Public/Util/SparseIndexCollectionTypes.h
Indexmap that supports dense or sparse storage, or a simple formula-based map (e.g. constant, identity, shift) For dense and sparse, the formula can be used to set default values.
struct FOptionallySparseIndexMap
int
DefaultOffset
Mapping to assign defaults for indices that are not explicitly assigned; computed as Index*DefaultScale + DefaultOffset
int
DefaultScale
TArray< int >
Dense
Storage used when map is dense
EMapType
MapType
Choice of storage backing the map
int
MaxIndex
Max index in map; -1 will leave the map unbounded (invalid for Dense maps)
TMap< int, int ...
Sparse
Storage used when map is sparse